1. Field of the Invention
The invention is relates to a method for fabricating a color filter, more particularly to a method for fabricating a color filter by using the theory of surface tension. The surface tension is very small when hydrophobic material is on hydrophobic surface and the surface tension is very large when hydrophobic material is on hydrophilic surface. It avoids to blurry with the printed hydrophobic color materials and can get fine color filter with excellent color reappearance when the surface of pixel area is a hydrophobic surface and the surface of non-pixel area is a hydrophilic surface.
2. Description of the Prior Art
In a conventional liquid crystal display (LCD) apparatus, two electrode substrates are faced with a cell gap. Each of the electrode substrates has electrodes that generate pixels. A liquid crystal layer is held between the two electrode substrates so that the peripheral portion of the liquid crystal layer is sealed. In this manner, the principal portions of the LCD apparatus are constructed.
In a LCD apparatus that can especially display a color image on the screen, a color filter is used. The color filter is constructed by disposing color cells of three primary colors or a plurality of hues such as R, G, and B (red, green, and blue) or Y, M, and C (yellow, magenta, and cyan) corresponding to individual pixels on at least one of the two electrode substrates.
Many fabricating methods of the color filters such as pigment dispersing method, dye dispersing method, electrodepositing method, and printing method have been proposed. In the pigment dispersing method, a pigment is dispersed to a layer to be colored and thereby a color filter is formed. In the dye dispersing method, a dye is dispersed to a layer to be colored and thereby a color filter is formed. In the electrodepositing method, a color filter is formed by electrodeposition. In the printing method, a coloring material of the color filter that is an ink is printed on a substrate using a printing plate such as an intaglio printing plate or an offset plate. The abovementioned methods have been practically used.
But, in such conventional fabricating methods, since the lithography process and the etching process are used repeatedly, the process of the color filter becomes very complicated. In addition, to deal with pixel sizes that are becoming smaller and smaller, the accuracy of the lithography process and the etching process should be improved. It is difficult to fabricate such color filters with high accuracy and high yield. Moreover, more than three times lithography process and the etching process are used to fabricate the color filter of RGB colors. The complication and cost of the above processes will increase accordingly.
In the printing method, although the etching technology is not directly used, the fabrication of the printing plates is very complicated. Moreover, in the printing method, it is difficult to form precise color filters that correspond to the sizes of fine pixels.
Recently, an inkjet printing method of a fine color filter has been proposed. However, when a color filter is formed by the inkjet print method, the sprayed coloring material may blur with another coloring material at a boundary region thereof so that it is difficult to reproduce clear colors. Thus, even if color filters with very high throughput are formed by an ink jet unit, the reappearance of colors of the color filters is low. Consequently, the color reappearance and display quality of color images of the LCD apparatus using the color filters fabricated by the said inkjet print method are inferior.
In the light of the state of the art described above, it is an object of the present invention to provide a method for fabricating a color filter which is immune to the problems of the conventional method for fabricating a color filter described above.
It is another object of this invention to provide a method for fabricating a color filter that the surface of pixel area is a hydrophobic surface and the surface of non-pixel area is a hydrophilic surface to avoid to blurry with the printed hydrophobic color materials and get fine color filter with excellent color reappearance.
It is a further object of this invention to provide a method for fabricating a color filter that the hydrophobic color material is easily printed on the hydrophobic surface of polysilicon layer or amorphous silicon layer irradiated with ultraviolet rays over the pixel areas of glass substrate and the hydrophobic color material is not easily printed on the hydrophilic surface of SiO2 layer irradiated with ultraviolet rays over the non-pixel area of glass substrate to avoid to blurry with the printed hydrophobic color materials and get fine color filter with excellent color reappearance.
In view of the above and other objects which will become apparent as the description proceeds, there is provided according to a general aspect of the present invention a method for fabricating color filter which comprises forming a dielectric layer on a substrate; forming a plurality of scan lines and a plurality of data lines on said dielectric layer to define a plurality of pixel areas and a non-pixel area; forming a hydrophobic surface on said plurality of pixel areas; forming a hydrophilic surface on said non-pixel area; and printing a hydrophobic color material on said plurality of pixel areas by inkjet printing method.
Base on the idea described above, wherein said scan lines and said data lines cross vertically.
Base on the aforementioned idea, the method for fabricating color filter further comprises a plurality of thin film transistors (TFTs) formed on said substrate.
Base on the idea described above, wherein said scan lines, said data lines and said TFTs are connected electrically.
In view of the above and other objects which will become apparent as the description proceeds, there is provided according to a general aspect of the present invention a method for fabricating color filter which comprises forming a dielectric layer on a substrate; forming a plurality of scan lines and a plurality of data lines on said dielectric layer to define a plurality of pixel areas and a non-pixel area; forming a hydrophilic surface on said plurality of pixel areas; forming a hydrophobic surface on said non-pixel area; and printing a hydrophilic color material on said plurality of pixel areas by inkjet printing method.
Base on the idea described above, wherein said scan lines and said data lines cross vertically.
Base on the aforementioned idea, the method for fabricating color filter further comprises a plurality of thin film transistors (TFTs) formed on said substrate.
Base on the idea described above, wherein said scan lines, said data lines and said TFTs are connected electrically.
In view of the above and other objects which will become apparent as the description proceeds, there is provided according to a general aspect of the present invention a method for fabricating color filter which comprises forming a dielectric layer on a substrate; forming a plurality of scan lines and a plurality of data lines on said dielectric layer to define a plurality of pixel areas and a non-pixel area; forming a SiO2 layer on said dielectric layer; irradiating said SiO2 layer with ultraviolet rays; forming a mask layer on said SiO2 layer; irradiating said mask layer with ultraviolet rays; removing said mask layer on said non-pixel area to expose said SiO2 layer; and printing a hydrophobic color material on said plurality of pixel areas by inkjet printing method.
Base on the idea described above, wherein said scan lines and said data lines cross vertically.
Base on the aforementioned idea, the method for fabricating color filter further comprises a plurality of thin film transistors (TFTs) formed on said substrate.
Base on the idea described above, wherein said scan lines, said data lines and said TFTs are connected electrically.
Base on the aforementioned idea, wherein the step of irradiating said SiO2 layer with ultraviolet rays further comprises inserting a first photomask above said substrate; and irradiating said SiO2 layer with ultraviolet rays through said first photomask.
Base on the idea described above, wherein the patterns of said first photomask over said plurality of pixel areas are opaque.
Base on the aforementioned idea, wherein said mask layer is selected from the group consisting of polysilicon and amorphous silicon.
Base on the idea described above, wherein the step of irradiating said mask layer with ultraviolet rays further comprises inserting a second photomask above said substrate; and irradiating said mask layer with ultraviolet rays through said second photomask.
Base on the aforementioned idea, wherein the pattern of said second photomask over said non-pixel area is opaque.
In view of the above and other objects which will become apparent as the description proceeds, there is provided according to a general aspect of the present invention a method for fabricating color filter which comprises forming a dielectric layer on a substrate; forming a plurality of scan lines and a plurality of data lines on said dielectric layer to define a plurality of pixel areas and a non-pixel area; forming a SiO2 layer on said dielectric layer; forming a mask layer on said SiO2 layer; removing said mask layer on said non-pixel area to expose said SiO2 layer; irradiating said substrate with ultraviolet rays; and printing a hydrophobic color material on said plurality of pixel areas by inkjet printing method.
Base on the idea described above, wherein said scan lines and said data lines cross vertically.
Base on the aforementioned idea, the method for fabricating color filter further comprises a plurality of thin film transistors (TFTs) formed on said substrate.
Base on the idea described above, wherein said scan lines, said data lines and said TFTs are connected electrically.
Base on the aforementioned idea, wherein said mask layer is selected from the group consisting of polysilicon and amorphous silicon.
Base on the idea described above, wherein the step of removing said mask layer on said non-pixel area to expose said SiO2 layer further comprises forming a photoresist layer on said mask layer; patterning said photoresist layer; and etching said mask layer that is not covered by said patterned photoresist layer.
In view of the above and other objects which will become apparent as the description proceeds, there is provided according to a general aspect of the present invention a method for fabricating color filter which comprises forming a dielectric layer on a substrate; forming a plurality of scan lines and a plurality of data lines on said dielectric layer to define a plurality of pixel areas and a non-pixel area; irradiating said substrate with ultraviolet rays; and printing a hydrophilic color material on said plurality of pixel areas by inkjet printing method.
Base on the idea described above, wherein said scan lines and said data lines cross vertically.
Base on the aforementioned idea, the method for fabricating color filter further comprises a plurality of thin film transistors (TFTs) formed on said substrate.
Base on the idea described above, wherein said scan lines, said data lines and said TFTs are connected electrically.
Base on the aforementioned idea, wherein said dielectric layer is a SiO2 layer.